Ink jet printing is important to the business community. Not only does improved success in this endeavor require the continuous updating and improvement of the equipment such as ink jet printers, but improvement of ink jet recording sheets for use with such equipment is important. Ink jet recording sheets generally contain a coating of a polymeric organic binder and a pigment. High resolution and high chroma are desirable properties for ink jet recording sheets. The sheets, in order to achieve these properties, have a thin receptor layer and a low binder to pigment ratio. Relatively thick coating layers tend to hide the dye color and decrease chroma. A problem with having low binder to pigment ratios is that many standard polymeric binders do not have adequate binding strength. Low binding strength results in the pigment in the coating layer dusting off the support. To date, polyvinyl alcohol crosslinked with borate has provided a good coating for ink jet recording sheets. However, the quick reaction of the borate with polyvinyl alcohol requires the coating of the borate and polyvinyl alcohol in separate layers. This in turn increases the expense of the recording sheet. Common polyvinyl alcohol crosslinking agents, e.g., amine formaldehyde condensates, require higher temperatures and longer times to develop strength than is available in standard coating machines used for coating paper.
It is desired that an improved ink jet recording sheet be prepared that provides high resolution as well as high chroma in a sheet having a thin receptor layer and a relatively low binder to filler or pigment ratio, the binder being of such strength that the pigment remains in the receptor layer without dusting off.